Vascular tissue removing device

ABSTRACT

A device for removing specimens of vascular tissue by scraping various portions of the area to be sampled is formed by a multistrand coil of wires, the ends of the wires being cut to define radially projecting, axially offset cutters, the device being guided by remote control means.

United States Patent [1 1 Willson et a1.

VASCULAR TISSUE REMOVING DEVICE Inventors: James K. V. Willson; Marshall Eskridge, both of PD. Box 7544, Mobile, Ala. 36607 Filed: May 17, 1971 Appl. No.: 144,029

Related US Application Data Continuation-impart of Ser. No. 50,182, June 26, 1970, Pat. No. 3,683,891.

US. Cl. 128/2 B, 128/305 Int. Cl A6lb 10/00 Field of Search 128/2 B, 2 M, 2 R, 128/D1G. 9, 304, 305, 310, 328; 15/104.3 G,

References Cited UNITED STATES PATENTS 566,110 8/1896 Wrigley 15/104.3 SN

[451 July 31, 1973 2,631,114 I 3/1953 O'Brien 15/1043 SN 2,694,822 11/1954 Murphy 15/1043 G 2,739,585 3/1956 Ayre 128/2 B 2,955,592 10/1960 MacLean 128/2 B 3,342,175 9/1967 Bulloch 128/2'B 3,452,740 7/1969 Muller 128/2 M 3,628,522 12/1971 Kato 128/2 B Primary Examiner-Kyle L. Howell Attorney-Christen & Sabol [57] ABSTRACT A device for removing specimens of vascular tissue by scraping various portions of the area to be sampled is formed by a multi-strand coil of wires, the ends of the wires being cut to define radially projecting, axially offset cutters, the device being guided by remote control 12 Claims, 9 Drawing Figures PATENIEU I915 3.749.085

'sum 1 OF 2 nv vE/vfoks JAMES K. v WILLSON MARSHALL [SKIP/06E ATTORNEYS PATENIEUJUW 19H 3.749.085

, sum 2 or a INVENTORS JAMES K. L WILLSON MARSHALL E SKR/OGE BYMMM ATTORNEYS VASCULAR TISSUE REMOVING DEVICE This application is a continuation in part of our earlier copending application, Ser. No. 50,182, filed June 26, 1970, entitled TISSUE AUGER, now US. Pat. No. 3683891.

The-present invention relates to means for performing biopsies and more particularly to a vascular tissue removing device having a scraping tool provided with a plurality of sharp cutters.

Such biopsy devices are used to remove vascular tissues, for example from the lung branches, with the purpose of examination to make a medical diagnosis. At present, devices are known which utilize a so-called auger" action similar to that employed by the common wood auger which resembles a flat strip twisted about its longitudinal axis and terminating in a radially disposed knife. However, all these devices are directed to the extraction of a tissue core from a defined location, whereas in some instances it is more interesting to obtain a tissue sample from the surface of a relatively wide area. This can but be achieved by scraping the de sired surface.

Such devices for removing specimens of tissue by scraping or rubbing are also known, for example in form of brushes, but the action of such tools is uncertain both as to effectiveness and to the amount of the specimen removed. Furthermore, the known devices are suitable for a longitudinal scraping action, but not for a rotating scraping action, since their considerable length and flexibility makes them inappropriate for transmitting a rotational torque.

It is, therefore, an object of the present invention to provide a vascular tissue removing device having a tissue scraping tool to be rotated and which can effectively scrape extended areas of the end or side walls of the branch of the cavitY to be examined and remove determined amounts therefrom.

It is another object of the invention to provide a device which can be guided and operated from the outside of a living body to be examined.

It is a further object of the invention to provide a de vice which can efficiently transmit a rotational torque from the outside of a living body to the operating tool in the inside of said living body.

To realize these objects the present invention comprises a vascular tissue removing device having a tissue scraping tool to be rotated around an axis and including a plurality of cutters substantially radially projecting with respect to this axis of rotation. In addition, the cutters may be partially axially offset with respect to the axis of rotation of the tool, so that tissue portions of different parts of a relatively wide area may be simultaneously scraped. There are several ways in which the tool may be guided to the location where it is to be used. It may be done by first inserting a hollow needle into the tissue to the location to be examined and the tool then inserted to that spot through the hollow. On the other hand, if the tissue to be examined lies within a branched cavity, such as the lungs, the tool may be attached to the end of a flexible deflecting probe and guided to the location by the probe.

Further, in one form of the invention, the tissue scraping tool forms the extremity of a flexible helical coilof wire which, in turn, may be guided to the area in question by means of a deflecting probe.

In addition, the invention also consists of an improved form of deflecting probe means having a multistrand helical coil to provide greater rotational torque for the tool than is possible by means of known deflecting probes and which, in addition, provides more accurate control of the directing of the probe means.

Other objects and advantages will be apparent after the reading the following description in connection with the drawings, in which:

FIG. 1 is a view in elevation, on a greatly enlarged scale, of one form of tissue scraping tool made in accordance with this invention;

FIG. 2 is an end elevation of the device of FIG. 1, showing the position of the cutting means;

FIG. 3 is an end elevation of a modified form of a scraping tool made in accordance with this invention;

FIG. 4 is a view in elevation of the tissue scraping device of FIG. 1, on a reduced scale, forming the extremity of an improved type of deflecting probe in accordance with the invention;

FIG. 5 is an enlarged fragmentary section of the bending portion of the improved deflecting probe;

FIG. 6 is a view in elevation of the tissue scraping device of FIG. 1 using a conventional probe solely as a guiding means;

FIG. 7 is a side elevation of a plastic catheter employed in inserting the probe into a branched cavity;

FIG. 8 is a side view of an assembly of two catheters, the scraping device of the invention and a conventional deflecting probe, which can be employed in exploring a branched cavity; and

FIG. 9 is a diagrammatic representation of the method employed in using the device of FIG. 8.

Referring now to the Figures, FIGS. 1 and 2 show a preferred embodiment of a tissue scraping tool according to the invention, indicated generally by numeral 11. This device comprises a single layer multistrand helically wound coil of wires, having preferably four wires 12, 13,14 and 15, and defining a leading end 16, an intermediate portion 17 behind said leading end and a trailing portion 18 behind said intermediate portion, said trailing portion 18 being only partially illustrated in FIG. 1. The four wires forming the scraping tool may be fabricated of fine stainless steel spring wire which is strong and substantially inert with respect to bodyand tissue fluids.

As an example, although not to be considered as a limitating one, each of the four spirally coiled wires, of round stainless steel may have an approximate diameter of 0.020 inch, while the outside diameter of the coil may be approximatey 0.090 inch. Where wire 15 reaches the intermediate portion 17 it is terminated in a sharpened and pointed tissue cutter which is slightly bent to define a cutter l9 projecting partially radially outwardly from said intermediate portion. In the direction towards the leading end 16 and in front of cutter 19 the coil only comprises wires l2, l3 and 14. Further on toward the leading end, preferably after two and a half turns, wire 14 is cut, in a similar way as wire 15, into a sharpened and pointed tissue cutter and is slightly bent to define a cutter 20 projecting partially radially outwardly from said intermediate portion. After another two and a half turns the remaining wires 12 and 13 are cut in the plane normal to the axis of the device into respective sharpened and pointed tissue cutters 21 and 22.

Thus, as the tool is rotated, both the first tissue cutters 21 and 22 arranged at the leading end 16, and the second tissue cutters l9 and 20 arranged at the intermediate portion 17 of the coil will simultaneously scrape different parts of the area to be sampled. The gaps 23 and 24, originated by the removal of the respective wires and 14 which have been cut off, and located between subsequent turns of the unremoved wires 14 and 12, and 13 and 12, respectively, will receive the scraped material and lead it to the interior of the coil, so that the risk of loosing the specimen while extracting the scraping device from the living body is completely eliminated. Moreover, the obtained specimen will comprise surface portions of an area whose size is at least equivalent to the distance between cutters 19 and 21. I

In addition, the cutters 21 and 22 located at the leading end of the tool permit not only a circumferential scraping of the lateral surfaces of a tissue portion but also the extraction of a tissue core, for example from the end surface of a lung branch positioned in a sub stantially normal plane to the axis of the scraping device.

While the described arrangement of the cutters is particularly suitable due to the symmetrical and regular location of the cutters, shown in FIG. 2, it is apparent that any other distribution of the cutters at the leading end and along the intermediate portion can be chosen without departing from the scope of the invention. Also, instead of four wires any desired number of wires can be utilized to define the cutters, the only requirement being that they project partially radially outwardly from the axis of the scraping device and that they are partially axially offset with respect to said axis. Thus, instead of forming the cutters at the ends of the wires of a coil, the scraping tool could be a cylindrical body made of steel sheet and provided with pointed portions projecting outwardly of said body.

According to another embodiment of the invention, shown in FIG. 3, the four wires of the multi-strand coiled wire have each the same length, and their terminal ends are cut off in a plane normal to the axis of the coil and may be bent outwardly to form a sort of rosette composed of four equi-angularly spaced sharpened cutters, 19', 20', 21' and 22', which may be used to scrape a tissue surface and to pierce and grip a small specimen of tissue for removal by withdrawal of the device in an axial direction. Preferably, in this embodiment the leading ends of the cutters are serrated.

Since the instruments just described represent a basic tool, the scraping device embracing the invention concept just described is capable of several modifications. For example, the tool as described may be employed to reach internal organs by the use ofa hollow needle provided with an angled tip and having an internal diameter large enough to aecomodate the present tissue scraping device therein for movement to the site of biopsy conducted by an elongated shank extending outwardly of the other end of the needle and for removal of the core specimens through the needle.

Another system for guiding the tool to the site for use and for manipulating it is to attach the tool to the extremity of a deflecting type probe such as is known as a Muller" wire. This type of device is particularly useful in exploring the various branches of the oral and nasal cavities. A typical Muller deflecting tip comprises a tightly wound wire probe having a central con- 4. trol wire passing therethrough. Over an area of flexure near the forward end of the tip, the coiled wires are reduced in diameter over adjacent half turns so that tension produced at the end of the tip by the control wire, causes deflection.

Deflecting type probes of the type discussed above are disclosed in U. S. Pat. No. 3,452,740 and No. 3,452,742, granted to W. F. Muller on July I, I969, while another form of device of this type is shown in U. S. Pat. No. 3,521,620 granted to W. A. Cook on July 28, 1970, and no claim is made to this form of deflecting probe per se.

According to the invention, the elongated trailing portion 18 which is adapted to guide the scraping tool to the site for use and to manipulate it comprises a single layer multi-strand helical coil, shown in FIGS. 1 and 4, which provides a greater rotational torque for a tool attached to the extremity thereof than is possible by means of the single wire of the known deflecting probes. According to a preferred embodiment, this trailing portion 18 located behind the intermediate portion 17 comprises the same four wires 12, 13, 14 and 15 which form the previously described tools, these wires having the same diameter and pitch of the helix and being wound into a four-strand helical coil, the turns of which lie closely adjacent each other, except for a portion of its length next to the end defining the guide section or flexure area 25, shown in FIG. 5, of the probe. The bending effect is accomplished in a known way, already described in connection with the Muller" wire, and is not part of the invention. The central core wire 26 is also conventional, lies inside the coil 18, and is soldered in 27 to the front end of the trailing portion 18. Thus, when the direction of the front portion of the probe is changed, it urges the attached device to point in the desired direction. The tool means, which extend beyond the end of said probe, can then be rotated to collect the desired specimen of tissue.

The capacity of transmitting a greater rotational torque results from the facts that the number of turns of each single helical wire decreases proportionally to the increase of the number of wires forming the multistrand coil, and that the elasticity of the coil depends, among other factors, from the number of turns of the wires.

Thus, this improved deflecting probe means is particularly useful in the embodiment of FIG. 4, since it offers an increased capability of transmitting rotational torque along the portion 18, which results in a better control of rotational torque from the control means to the tip portion.

It should also be obvious that this improved deflecting probe means comprising a multi-strand helical coil, according to the invention, can be used in connection with brushes, augers or any other kind of tools which require a rotational movement of the deflecting probe means.

The extremity of the deflecting probe is inserted, together with the tissue cutters, into the vascular system from the exterior ofa living body, for guidance and operation of the tissue cutters from the exterior of said body by manual manipulation of the elongated trailing portion. The other end of the deflecting probe to be disposed exteriorly of a living body is provided with manual control means 28 having one element 29 fixedly connected with the single layer wire coil 18 for exerting positive rotation to a scraping tool 11 at the leading end of the coil, and a second element 30 is fixedly connected with said straight flexible wire 26 for exerting axial compression on the flexurc area.

In another form of the scraping device a conventional deflecting tip, such as a Muller wire, or the deflecting probe of the present invention, is employed solely as a guide means. The scraping device is constructed generally as previously described with the exception that the trailing portion consists of a uniform multistrand wire coil, without having a flexure area nor a central core wire, which passes over into the scraping tool 11 having an intermediate portion 17 provided with the cutters 19 and 20 and a leading end 16 pro vided with the cutters 21 and 22.

The inner diameter of the tool according to this modification is such that the deflecting probe means may be pushed completely through the tool to serve as a guide to reach the desired location, and the length of the coiled wire forming the trailing portion of the tool is such that it will extend along the entire length of the deflecting probe means to permit rotation of the tool, either when the deflecting tip has been partially, or completely, removed from the interior of the trailing portion. With this form of the invention, instead of attaching the cutter 11 to a deflecting probe and using the deflecting probe to both guide and rotate the cutter, the deflecting probe 31 may be used solely to guide the cutter II to the remote portion of the cavity, after which the probe can be removed and the cutter manipulated by manually rotating the other extremity of the trailing portion 18, as shown in FIG. 6.

In this case the inside diameter of the helix forming the trailing portion 18 and cutter 11 should be such that the entire length of the device may be easily slid over the exterior of a deflecting probe 31, and the length of the coil should be sufficient to permit the remote end of the coiled wire to extend outwardly of the cavity into which the tool is inserted and to be secured to an annular portion 32. By manually gripping the annular portion 32 the cutter and trailing portion may be rotationally and axially manipulated, independently of the deflecting probe means indicated generally by numeral 31. In practice, the length of the coil does not usually exceed 2 to 3 feet.

FIGS. 7 to 9 show a particularly useful application of the scraping device of FIG. 6 and a method for removing tissue from the interior of a living body usingthis particular combination.

It is known that tubular devices to be inserted into living bodies, commonly known as catheters, may be manufactured of a semi-rigid material such as plastic, and that during the manufacture of these plastic cathe ters any desired form may be given to them, so that this form remains inherent to the catheter even ifdue to its semi-rigid nature the catheter is forced to momentarily adopt a different form.

This quality is illustrated in FIG. 7 which shows a J- shaped catheter 33, that is, a catheter which has the tendency to bend into a .l-form defining a substantially right angle at its leading portion. However, due to its semi-rigid nature this catheter can be forced into a straight line indicated by dotted lines.

FIG. 8 shows the combination of an .l-shaped catheter 33 with a straight catheter 34, the outer diameter of catheter 33 being slightly smaller than the inner diameter of catheter 34, so that both catheters are in axially and rotatably slidable' relationship to each other.

Within catheter 33 a scraping device according to the invention, and particularly as shown in FIG. 6, is located in axially and rotatably slidable relationship thereto. That is, the inner diameter of catheter 33 is slightly larger than the outer diameter of the trailing portion 18 and the scraping tool I]. As already mentioned, a conventional deflecting probe 3] is slidably located within the scraping device.

A method of using the above described combination to remove tissue specimens from the interior of a living body consists in first inserting a normally J-shaped semi-rigid catheter 33 into the interior of a larger straight catheter 34, so that catheter 33 momentarily adopts the straight form of catheter 34. Both catheters are inserted into the oral cavity 35 of a body until the leading end of catheter 34 reaches a primary branch in said cavity, indicated for example with 36 in FIG. 9. Catheter 33 is now axially oriented and advanced with respect to catheter 34, so that its leading end protrudes from catheter 34, bends to recover its inherent form and enters said branch 36. Subsequently, a longitudinally and angularly basically inflexible but radially flexible biopsy device, such as the tissue scraping device according to the invention is inserted into said catheter 33 and advanced into the primary branch 36 beyond the end of catheter 33. The bent end portion of catheter 33 thus provides an accurate and constant guide for the advancing leading portion of tool 11 into a secondary branch 37, to the desired area 38 to be sampled, by the guiding action of the deflecting probe 31. When the tool 11 has reached the area 38, as indicated by dotted lines, the probe 31 is partially or totally withdrawn, so that the tool can be rotated from the outside of the body, as described above, to capture a tissue specimen. Due to the ability of the device according to the invention to transmit rotational torque, and to the design of the tool, a desired amount of tissue can be easily removed from the area 38 and be effectively withdrawn when the tool is retrieved from the cavity through the catheters.

It will be understood that this method described above can also be used in connection with a device as shown in FIG. 4, where the scraping device and the deflecting probe are unitary.

It will further be understood that while the examples described illustrate various modifications of the invention, they are not to be considered as limiting. The dimensions and types of materials may be varied within reasonable limits.

The claims are:

l. A vascular tissue removing device comprising a tissue scraping tool to be rotated around an axis and having a plurality of cutters substantially radially projecting with respect to said axis of rotation, means for transmitting a rotational torque and a longitudinal movement to said tool and connected to said plurality of cutters, said means comprising a single layer multistrand closely spaced helically wound coil of wires, and means for guiding the direction of said longitudinal movement.

2. A device as defined in claim 1, wherein said plurality of cutters are partially axially offset along the longitudinal axis of the tool.

3. A device as defined in claim 2, wherein said means for guiding said longitudinal movement of the tool includes a tubular element surrounding said tool, and said means for transmitting a rotational torque and a longitudinal movement to said tool includes an elongated shank extending outwardly of the other end of the tubular element.

4. A device as defined in claim I, wherein said plurality of cutters comprises the terminal ends of the wires of the helically wound coil, said coil being cut off in a plane normal to the axis of the helix and said terminal ends projecting partially radially outwardly from the periphery of said coil to define a rosette-shaped tool.

5. A device as defined in claim 1, wherein said single layer multi-strand helically wound coil of wires has a leading end, an intermediate portion behind the leading end and an elongated trailing portion behind the intermediate portion, at least one of said wires terminating at the leading end of the coil in a first sharpened tissue cutter, and at least one of the other wires of the coil terminating in a second sharpened tissue cutter projecting partially radially outwardly from said intermediate portion behind said first cutter.

6. A device as defined in claim 5, wherein each ofthe wires forming said single layer coil terminates in a sharpened tissue cutter.

7. A device as defined in claim 6, wherein at least two of said wires forming said coil terminate at the leading end of the coil in sharpened tissue cutters.

8. A device as defined in claim 7, wherein at least two of the wires forming said tissue cutters terminate at locations spaced from each other axially of the coil.

9. A device as defined in claim 8, wherein said single layer multi-strand helically wound coil comprises at least four helical wires with substantially the same diameter and the same pitch of the helix, at least two of said wires terminating in sharpened tissue cutters axially spaced from each other and from the leading end of the coil.

10. A device as defined in claim 5, wherein said elongated trailing portion is radially flexible for insertion of the tissue cutters into the vascular system from the exterior of a living body and for operation of said tissue cutters from the exterior of said body by manual manipulation of said elongated trailing portion.

11. A device as defined in claim 10, wherein the turns of said helical wires in said trailing portion are disposed in axially abutting relation, certain of said turns comprising a direction--changing flexure area, the axial thickness of adjacent portions of each of the turns of wire at said flexure area being reduced over approximately one-half of the adjacent circumferences thereof, a straight flexible wire being connected at one end with the extremity of the trailing portion adjacent said intermediate portion for exerting axial compression on the flexure area for altering the longitudinal curvature of said flexure area of the trailing portion.

12. A device as defined in claim 11, wherein the extremity of said trailing portion to be disposed exteriorly ofa living body is provided with manual control means, said control means being fixedly connected with said single layer wire coil for exerting positive rotation to said cutters at the leading end of the coil, and with said straight flexible wire for exerting axial compression on the trailing portion. 

1. A vascular tissue removing device comprising a tissue scraping tool to be rotated around an axis and having a plurality of cutters substantially radially projecting with respect to said axis of rotation, means for transmitting a rotational torque and a longitudinal movement to said tool and connected to said plurality of cutters, said means comprising a single layer multistrand closely spaced helically wound coil of wires, and means for guiding the direction of said longitudinal movement.
 2. A device as defined in claim 1, wherein said plurality of cutters are partially axially offset along the longitudinal axis of the tool.
 3. A device as defined in claim 2, wherein said means for guiding said longitudinal movement of the tool includes a tubular element surrounding said tool, and said means for transmitting a rotational torque and a longitudinal movement to said tool includes an elongated shank extending outwardly of the other end of the tubular element.
 4. A device as defined in claim 1, wherein said plurality of cutters comprises the terminal ends of the wires of the helically wound coil, said coil being cut off in a plane normal to the axis of the helix and said terminal ends projecting partially radially outwardly from the periphery of said coil to define a rosette-shaped tool.
 5. A device as defined in claim 1, wherein said single layer multi-strand helically wound coil of wires has a leading end, an intermediate portion behind the leading end and an elongated trailing portion behind the intermediate portion, at least one of said wires terminating at the leading end of the coil in a first sharpened tissue cutter, and at least one of the other wires of the coil terminating in a second sharpened tissue cutter projecting partially radially outwardly from said intermediate portion behind said first cutter.
 6. A device as defined in claim 5, wherein each of the wires forming said single layer coil terminates in a sharpened tissue cutter.
 7. A device as defined in claim 6, wherein at least two of said wires forming said coil terminate at the leading end of the coil in sharpened tissue cutters.
 8. A device as defined in claim 7, wherein at least two of the wires forming said tissue cutters terminate at locations spaced from each other axially of the coil.
 9. A device as defined in claim 8, wherein said single layer multi-strand helically wound coil comprises at least four helical wires with substantially the same diameter and the same pitch of the helix, at least two of said wires terminating in sharpened tissue cutters axially spaced from each other and from the leading end of the coil.
 10. A device as defined in claim 5, wherein said elongated trailing portion is radially flexible for insertion of the tissue cutters into the vascular system from the exterior of a living body and for operation of said tissue cutters from the exterior of said body by manual manipulation of said elongated trailing portion.
 11. A device as defined in claim 10, wherein the turns of said helical wires in said trailing portion are disposed in axially abuTting relation, certain of said turns comprising a direction--changing flexure area, the axial thickness of adjacent portions of each of the turns of wire at said flexure area being reduced over approximately one-half of the adjacent circumferences thereof, a straight flexible wire being connected at one end with the extremity of the trailing portion adjacent said intermediate portion for exerting axial compression on the flexure area for altering the longitudinal curvature of said flexure area of the trailing portion.
 12. A device as defined in claim 11, wherein the extremity of said trailing portion to be disposed exteriorly of a living body is provided with manual control means, said control means being fixedly connected with said single layer wire coil for exerting positive rotation to said cutters at the leading end of the coil, and with said straight flexible wire for exerting axial compression on the trailing portion. 